Influenza virus molecules set immune response into overdrive

Researchers at the University of Cambridge and the University of Oxford have discovered a new molecule that plays a key role in the immune response that is triggered by influenza infections. The molecule, a so-called mini viral RNA, is capable of inducing inflammation and cell death, and was produced at high levels by the 1918 pandemic influenza virus. The findings appear in Nature Microbiology. Influenza is one of the main infectious diseases in humans. Seasonal influenza viruses account for about 650,000 deaths per year, whereas pandemic strains such as the 1918 H1N1 virus have been linked to 50-100 million deaths worldwide. Highly pathogenic avian influenza viruses such as the H5N1 and H7N9 strains have a mortality rate of about 50% in humans. The reasons for difference in disease severity and lethality caused by seasonal influenza viruses on the one hand, and pandemic and highly pathogenic avian influenza viruses on the other hand, is still poorly understood.